1. Field of the Invention
This invention relates to a data base searching system and more particularly to a system which enables a data base to be interrogated at very high speed.
2. State of the Art
It has been proposed for data base searching systems to include a plurality of processing elements which simultaneously compare respective data records with a common data item being searched for. The processing elements of such systems include microprocessors and are therefore complex. Furthermore, communications sub-systems are required between the various processing elements, and an interrogations sub-system is required in order to interrogate the processing elements so that the results of the search procedure can be established.
Another system which has been proposed, called Content Addressable Memory, includes a comparator for each bit in the memory: this system can only provide equality comparisons and has fixed field and record sizes and more importantly is very expensive to produce because CAM memory cells are an order of magnitude larger than dynamic RAM.